Prior art night lights designed to be plugged directly into electric wall outlets have one major problem. The maximum and minimum blade friction allowable by electric equipment regulatory authorities (e.g., UL and CSA) is specified to permit reasonable convenience for the user in plugging and unplugging the blades from standard electric wall outlets. Unfortunately, however, this ease in removing the night light from the outlet increases its safety hazard. Babies and young children are attracted to lighted objects, particularly objects accessible at eye level near the floor. Moreover, night lights are generally larger than normal plugs, thus providing a large gripping surface for crawling infants and children. It is therefore possible for infants and children to partially remove the night light from the outlet and insert their small fingers into contact with the live power blades, exposing themselves to severe electric shock.
One of the present applicants, R. G. Dickie, has filed a patent application, Ser. No. 08/220,302 filed Mar. 28, 1994, on a cover plate assembly for electric outlets which uses a wall plate to be screwed to the outlet itself and a cover plate attached to the wall plate by ridges on the outer periphery of the cover plate which engage mating ridges on the outer periphery of the wall plate by snap action. The cover plate engages the wall plate with a significantly greater force than the normal blade friction of an electric plug, yet is readily removable by a determined pull on the cover plate.